How changelog is detected as added or removed?

Changelog compares latest inventory with last collected inventory against unique attribute as part of specific parameter collection. Please note that changelog is calculated for specific parameters and attributes enabled in the schema configuration. For example: Physical memory parameter may collect attributes like Bank Label, Capacity, Memory Type, etc. However, change log might be enabled on attributed Bank Label and Capacity alone.

In above case unique attribute is Bank Label so if Bank Label is not appearing in latest inventory and was available in previous inventory, changelog detects it as removed. If it finds new Bank Label in latest inventory which is not available in previous inventory, changelog detects it as added. If it finds bank label in latest inventory is available in previous inventory but capacity attribute is changed from 1MB to 2MB, then it detects it as change however instead of detecting it as modified, this also will be detected as old instance deleted and new instance added and currently this is the behavior.